Q. I just bought a natural cleaner and it contains LINEAR SULFONATE. Do you know anything about this? I have seen it compared to SLS's but maybe as a better option? I just want to make sure that it is not as equally carcinogenic - or that it is not bad!THANKS!

Tiffany

A. Thanks for your question, Tiffany!

It turns out that "Linear Sulfonate" is not just one chemical, but a blend of several chemicals all in the same family. I'm assuming the product you're looking at is Biokleen, as they claim on their website "Linear Sulfonate is a propriety blend of vegetable based surfactants." While their blend is proprietary (read: not disclosed), we can take an educated guess at what this "Linear Sulfonate" is.

There is a group of surfactants (detergents) that are called Linear Alkylate Sulfonates. Traditionally, a blend of compounds are sold under the name Linear Alkylbenzene Sulfonate (commonly abbreviated LAS).

Decylbenzene sulfonic acid, sodium salt

Dodecylbenzene sulfonic acid, sodium salt

Tridecylbenzene sulfonic acid, sodium salt

Undecylbenzene sulfonic acid, sodium salt

C10-16 Monoalkylbenzene sulfonic acid, sodium salt

C10-13 Alkylbenzene sulfonic acid, sodium salt

C10-14 Alkyl deriv benzene sulfonic acid, sodium salt

C10-14 Monoalkylbenzene sulfonic acid, sodium salt

C10-13 Alkyl deriv benzene sulfonic acid, sodium salt

This blend of chemicals commonly known as LAS is likely what this "Linear Sulfonate" listing refers to.

Toxicity

LAS can be acutely toxic when ingested or applied to skin at very high amounts. It is most toxic when inhaled in powder form, with mortality occurring at a particle concentration of 310 mg/m3. This concentration would likely only happen in an industrial setting, however, not posing a risk in household use as you would use it in a dishwasher or laundry soap.

Irritation

At low concentrations (up to 2.5%), LAS typically does not exhibit skin irritancy, but at 5% it's moderately irritating and severely irritating at a 50% concentration. Eye irritation can occur as well, but is easily reversed by flushing with water. This study found it to be less absorbable by skin than SLS. (Source)

Carcinogenitiy/Mutagenity

Not found to be a carcinogen or mutagen.

Reproductive Toxicity

Not found to be a genotoxin or estrogen mimicker. However, in high amounts, it was found to increase the estrogenic effects of other pollutants in aquatic life. (Source)

It is found to be highly toxic to acquatic life, but is also highly biodegradable. (Source)

So, all in all, as long as you're not exposed to high amounts of LAS, I would consider it to be relatively safe as used in a laundry detergent or dishwasher soap. Because of its irritancy and potential for moderate toxicity, however, I would avoid it in a personal care product.